Helicobacter pylori (Hp) infection is the main reason for the chronic active gastritis and peptic ulcer in children. Increased evidences show that Hp plays an important role in a variety of extraintestinal diseases in children as well. There is a close relationship between Hp infection and iron deficiency anemia, idiopathic thrombocytopenic purpura and growth retardation. In this article, the correlation between Hp infection and several extraintestinal diseases is reviewed.